Tyrants are giant demons with immense power and resistance to damage from the front. These guys will only take damage from a crack in their back or on the top of their heads. The best thing to do is dodge their attack, use the Ophion Demon Pull Ability on their backs, and attack until they start smoking. Once they start smoking, use the Ophion Angel Lift Ability on their back to get up close and start hacking away. They can also be knocked into the air by a fully charged uppercut with the Eryx, but only while they're charging at you. This opens the Tyrant up for aerial combos.